I actually had Classic Auto Air in Tampa rebuild my high pressure hose. I had to send them a core so they could salvage the end fittings. Hose came back looking show room new for something like a $100+. I highly recommend them. Johnrex
I'm a believer in Powermaster. I have one on my 1964. Great technical service is a phone call away. If you have any questions, call Brady at 630-957-4019.
Just my data point, I bought a new 1969 Electra with the 430 engine. I drove it a 175,000 miles and had no engine problems. I ran good oil and changed it often. I knew about the redesign in 1970 because of the oiling problem but didn't experience any problem.
I am in agreement with Ed. A few other brands that meet your needs would be Brad Penn, Driven (formerly Joe Gibbs), TORCO, Royal Purple and Amsoil. They tend to be a bit more expensive than the Mobil 1 but are fine products.
You should use a mineral based oil for break-in. Do not use synthetic until you have run the engine at least for 500 miles. There are several very good brand of break-in oil like Driven which is the Joe Gibbs development, Royal Purple or others.
Don't forget that in the day, folks traded every couple years. Cars weren't good enough to keep like they are today. A 100K car was a car rare exception!
I checked the belts on my '64 which I know is original. I have the "square" male end. The tag on the belt: Model RCF-50-C 1964 Hamill Mfg. Co, Washington, Michigan
I ran my '64 with a Pertronix coil and ignition with the 8-10 VDC for a while with no problems. I since am using the 12-14 VDC that they recommend. Might be a temperature sensitive secondary winding in the coil. Swap out the coil first.
The first photo shows the connectors to the blower relay which I don't see installed. The relay mounts to the two small screws on the inner fender panel.
I like the idea of the 15W-50 because my engine has 86,000 miles. You need a heavier weight oil when you have increased bearing clearance which that many miles yields. That heavier weight will cost you a little in economy but I'm not driving a Riviera for that! I would consider a lighter weight for a rebuilt motor. I have been running the 15W-50 for at least 10 years and never had an oil leak. When synthetics first came out, the seals did not swell as much as with the mineral base oils. Mobil quickly solved that problem years ago. The reduced friction that the synthetics provide can reduce your oil temperature 20 degrees. That is good for the motor.
I attended a seminar at SEMA on modern oils for flat tappet engines and what Ed quoted was agreed to by all the major producers and experts who were on the panel. Too much ZDDP is not a good thing!
I think you will find that the Mobil I 10W-30 does not have the level of ZDDP that is recommended for our old cars. There are several Mobil1s that do, I use 15W-50 in my '64.